WO2019033998A1

WO2019033998A1 - Method for regulating evaporation temperature of indoor unit of air conditioner, and air conditioner

Info

Publication number: WO2019033998A1
Application number: PCT/CN2018/099942
Authority: WO
Inventors: 曹朋; 李立民; 冯涛; 武连发; 张仕强
Original assignee: 格力电器（武汉）有限公司; 珠海格力电器股份有限公司
Priority date: 2017-08-14
Filing date: 2018-08-10
Publication date: 2019-02-21
Also published as: CN107477780A

Abstract

A method for regulating the evaporation temperature of an indoor unit (1) of an air conditioner, and the air conditioner. The method comprises the following steps: determining whether the ambient temperature at where the indoor unit (1) is located is greater than or equal to a dew point temperature; if the ambient temperature is less than the dew point temperature, then reducing the degree of openness of a first throttling element (12) arranged on a liquid pipe (11) of the indoor unit (1), thus reducing the volume of a liquid refrigerant entering a heat exchanger (3) of the indoor unit (1); if the ambient temperature is greater than or equal to the dew point temperature, then reducing the degree of openness of a second throttling element (14) arranged on a gas pipe (13) of the indoor unit (1), thus reducing the outflow speed of a gaseous refrigerant from the gas pipe (13). The regulation of the evaporation temperature of the indoor unit (1) is implemented by regulating the degree of openness of the first throttling element (12) and that of the second throttling element (14), thus satisfying different demands for cooling and dehumidification in different rooms.

Description

Method for adjusting evaporation temperature of air conditioner indoor unit and air conditioner

This application is based on the CN application number of 201710691321.4, and the application date is August 14, 2017. The disclosure of the present application is hereby incorporated by reference.

Technical field

The present disclosure relates to the field of air conditioning, and in particular to a method for adjusting an evaporation temperature of an indoor unit of an air conditioner and an air conditioner.

Background technique

Large central air conditioners are often used in high-rise buildings. The outdoor unit of the large central air conditioning unit is installed on the top floor of the building, and the indoor unit is distributed on each floor of the building. For high-rise buildings, the air temperature and humidity in each room are different, so the temperature and humidity of the air adjusted during air conditioning operation are different.

In high-rise buildings, the rooms on the ground floor are relatively humid, and the room has less demand for refrigeration and has a greater demand for dehumidification. The room temperature on the upper floors is high and the air is dry. The room has a large demand for refrigeration and the demand for dehumidification is small. So how to realize the different needs of multiple rooms in a multi-line connection has become an urgent problem in the industry.

Summary of the invention

One of the objects of the present disclosure is to provide a method for adjusting the evaporation temperature of an indoor unit of an air conditioner and an air conditioner for realizing evaporation temperature adjustment of each indoor unit having a plurality of indoor unit units such as a central air conditioner.

The present disclosure provides a method for adjusting an evaporation temperature of an indoor unit of an air conditioner, comprising the steps of:

Determining whether the ambient temperature of the indoor unit is higher than or equal to the dew point temperature;

If the ambient temperature is lower than the dew point temperature, reducing the opening of the first throttling element located on the liquid pipe of the indoor unit to reduce the amount of liquid refrigerant entering the heat exchanger of the indoor unit; if the ambient temperature is high At or equal to the dew point temperature, the opening of the second throttle element located on the air tube of the indoor unit is reduced to reduce the velocity of the gaseous refrigerant flowing out of the heat exchanger of the indoor unit.

In some embodiments, if the ambient temperature is below the dew point temperature, the opening of the second throttle element of the air tube disposed in the indoor unit is maintained.

In some embodiments, if the ambient temperature is higher than or equal to the dew point temperature, the opening of the first throttling element of the liquid pipe provided to the indoor unit is maintained.

In some embodiments, the opening of the first throttle element on the indoor unit fluid tube is reduced in a manner proportional to the difference between the dew point temperature and the ambient temperature.

In some embodiments, the opening of the second throttle element on the indoor airway is reduced in a manner proportional to the difference between the ambient temperature and the dew point temperature.

Another embodiment of the present disclosure provides an air conditioner, including:

a plurality of parallel indoor units, at least one of the liquid tubes of the indoor unit is provided with a first throttle element, and a gas tube of the indoor unit is provided with a second throttle element;

Wherein the first throttling element is configured to reduce the opening degree when the ambient temperature is lower than the dew point temperature to reduce the amount of liquid refrigerant entering the heat exchanger of the indoor unit; the second throttling element is used for The opening degree is decreased when the ambient temperature is higher than or equal to the dew point temperature to reduce the velocity of the gaseous refrigerant flowing out of the heat exchanger of the indoor unit.

In some embodiments, each of the liquid tubes of the indoor unit is provided with one first throttling element, and each of the indoor units has a second throttling element.

In some embodiments, the first throttling element comprises an electronic expansion valve; and/or the second throttling element comprises an electronic expansion valve.

In some embodiments, the first throttling element and the second throttling element are the same.

In some embodiments, the air conditioner further comprises:

And a controller coupled to the first throttle element and the second throttle element for adjusting an opening degree of the first throttle element and the second throttle element.

In some embodiments, the air conditioner further comprises:

a temperature detecting device for detecting an ambient temperature at which the indoor unit is located, and/or,

A humidity detecting device for detecting the humidity of the environment in which the indoor unit is located.

In some embodiments, the air conditioner comprises a central air conditioner.

The method for adjusting the evaporation temperature of the central air conditioner indoor unit provided by the above technical solution separately sets the first throttle element and the second throttle element for the indoor unit that needs to adjust the evaporation temperature. When the cooling requirement is large, it is necessary to extend the residence time of the refrigerant in the indoor heat exchanger and reduce the velocity of the gaseous refrigerant flowing out of the indoor air pipe. Therefore, it is necessary to reduce the opening degree of the second throttle element to increase the indoor temperature. The amount of refrigerant in the machine reduces the temperature of the air and improves the cooling effect. When the dehumidification demand is large, it is necessary to reduce the amount of liquid refrigerant entering the indoor unit heat exchanger. Therefore, it is necessary to reduce the opening degree of the first throttling element, and reduce the amount of liquid refrigerant in the indoor unit. When the air volume is constant, after the refrigerant evaporates, The temperature of the outlet air rises, which can remove both humid air and a certain cooling effect. It can be seen that the above technical solution conveniently adjusts the evaporation temperature of the indoor unit by adjusting the opening degree of the first throttling element and the second throttling element, satisfies different cooling and dehumidification requirements of different rooms, and ensures the room where the indoor unit is located. Comfort.

DRAWINGS

1 is a schematic flow chart of a method for adjusting an evaporation temperature of a central air conditioner indoor unit according to an embodiment of the present disclosure;

2 is a schematic diagram of a partial principle for adjusting a central air conditioner indoor unit according to an embodiment of the present disclosure;

FIG. 3 is a schematic diagram of a principle for adjusting a central air conditioner according to an embodiment of the present disclosure.

Detailed ways

The technical solution provided by the present disclosure will be described in more detail below with reference to FIGS. 1 to 3.

Both refrigeration and dehumidification operations correspond to the refrigeration cycle of the air conditioner. The evaporation temperatures required for the refrigeration and dehumidification cycles are different. Embodiments of the present disclosure provide a method for adjusting an evaporating temperature of an indoor unit of an air conditioner, which is determined according to a difference between an ambient temperature and a dew point temperature of each indoor unit 1 under the premise that the low pressure of the outdoor unit of the system is constant. The evaporation temperature of the indoor unit 1. Referring to Figures 2 and 3, the central air conditioner includes an outdoor unit 6 and a plurality of indoor units 1, each of which is independent. The adjustment method of the embodiment of the present disclosure is for individually adjusting the evaporation temperature of each indoor unit 1.

The above adjustment method includes the following steps:

Step S10: determining whether the ambient temperature of the indoor unit 1 is higher than or equal to the dew point temperature.

The dew point temperature refers to the temperature at which the air cools to saturation without changing the water vapor content and the gas pressure.

The ambient temperature changes in real time, such as detecting the ambient temperature in real time through the sensing element. In general, for a particular indoor unit 1, the room in which it is located needs to be dehumidified or cooled. However, in some cases, the room needs to be dehumidified before cooling for a while; or the room is cooled first and then dehumidified after a while. In such an environment where both dehumidification and refrigeration are required, first, according to the relationship between the ambient temperature and the dew point temperature, what kind of operation is required, and then the first throttling element 12 and the second section are required before another operation is required. The flow element 14 is reset and then another operation is performed. There are two possible situations: dehumidification-reset-cooling, cooling-reset-dehumidification.

Step S20, if the ambient temperature is lower than the dew point temperature, the opening degree of the first throttle element 12 located on the liquid pipe 11 of the indoor unit 1 is reduced to reduce the amount of liquid refrigerant entering the heat exchanger 3 of the indoor unit 1.

In the above step S20, when the ambient temperature is lower than the dew point temperature, the ambient temperature is low, condensation may occur, and dehumidification is required. In this state, the opening degree of the first throttle element 12 is reduced, the amount of liquid refrigerant entering the heat exchanger 3 of the indoor unit 1 is reduced, the humidity in the room is quickly lowered, the air temperature is maintained, the dehumidification effect is improved, and At the same time achieve a certain cooling effect.

Further, in the above step S20, the method further includes the step of keeping the opening degree of the second throttle element 14 located on the air tube 13 of the indoor unit 1 unchanged if the ambient temperature is lower than the dew point temperature. That is, if the ambient temperature is lower than the dew point temperature, the opening degree of the first throttle element 12 on the liquid pipe 11 of the indoor unit 1 is reduced and the opening degree of the second throttle element 14 located on the air tube 13 of the indoor unit 1 is not maintained. The change is made to reduce the amount of liquid refrigerant entering the heat exchanger 3 of the indoor unit 1. This method is easy to implement, and accurately grasps the amount of refrigerant to be adjusted, and achieves precise adjustment of the evaporation temperature.

Further, in the above step S20, the reduced opening degree of the first throttle element 12 on the indoor unit liquid pipe 11 is proportional to the difference M, and the difference M is equal to the difference between the dew point temperature and the ambient temperature. The larger the difference M, the larger the opening of the first throttle element 12 on the indoor unit liquid pipe. On the contrary, the smaller the difference M is, the smaller the opening degree of the first throttle element 12 on the liquid pipe 11 of the indoor unit 1 is reduced.

Step S30, if the ambient temperature is higher than or equal to the dew point temperature, the opening degree of the second throttle element 14 located on the air tube 13 of the indoor unit 1 is reduced to reduce the flow of the gaseous refrigerant from the heat exchanger 3 of the indoor unit 1. speed.

If the ambient temperature is higher than or equal to the dew point temperature, it means that the temperature in the room is high and there is no need to dehumidify, but it is optional whether to cool. Since the low-pressure control of the central air-conditioning outdoor unit has been determined, by reducing the opening degree of the second throttle element 14 located on the air tube 13 of the indoor unit 1, the amount of refrigerant in the indoor unit 1 is increased, and the amount of heat absorbed from the outdoor unit is increased. Thereby achieving a cooling effect that reduces the outlet air temperature.

In the above step S30, further comprising the step of maintaining the opening degree of the first throttle element 12 located on the liquid pipe 11 of the indoor unit 1 unchanged. That is, if the ambient temperature is higher than or equal to the dew point temperature, the opening of the second throttle element 14 located on the air tube 13 of the indoor unit 1 is reduced and the first throttle element 12 located on the liquid tube 11 of the indoor unit 1 is maintained. The opening is unchanged. This method is easy to implement, and can accurately grasp the amount of refrigerant to be adjusted, and then accurately adjust the evaporation temperature.

In the above step S30, the reduced opening degree of the second throttle element 14 on the air tube 13 of the indoor unit 1 is proportional to the difference N, and the difference N is equal to the ambient temperature minus the dew point temperature. That is, the larger the difference N obtained by subtracting the dew point temperature from the ambient temperature, the larger the opening degree of the second throttle element 14 on the air tube 13 of the indoor unit 1 is reduced. On the contrary, the smaller the difference N obtained by subtracting the dew point temperature from the ambient temperature, the smaller the opening degree of the second throttle element 14 on the air tube 13 of the indoor unit 1 is reduced.

In the low-floor room, as the refrigerant enters the indoor unit 1 from the outdoor unit, the refrigerant flows downward, and the amount of refrigerant in the connecting pipe becomes less and less. Thus, in the case where the unit indoor unit 1 is fully opened, people in the floor room often feel that there is no air in the air conditioning cooling/heat condition. In this case, by the method provided by the above technical solution, the refrigerant in the indoor unit 1 is increased by reducing the number of steps of the second throttle element 14. During the cooling mode cycle, the low temperature liquid refrigerant of the indoor unit 1 increases, resulting in a decrease in the outlet air temperature and a cooling effect.

In a humid room, it is necessary to reduce the humidity while ensuring that the air temperature is substantially constant, and the number of steps of the first throttle element 12 is reduced. In this state, the first throttle element 12 of the indoor unit 1 no longer performs PID control, but according to the indoor The machine 1 evaporates temperature control to reduce the amount of liquid refrigerant in the indoor unit 1. When the air volume output from the fan 2 is constant, after the refrigerant evaporates, the outlet air temperature rises, and the control evaporation temperature is about 13 ° C. In this state, the outlet air temperature is between 17 ° C and 19 ° C, which removes the humid air and ensures that Cooling effect.

It can be seen that the multi-indoor air conditioning control method provided by the above technical solution realizes different temperature and humidity requirements in different rooms, and at the same time realizes detection and correction to meet the air blowing demand of different rooms.

Referring to FIG. 2 or FIG. 3, further, the first throttle element 12 includes a first electronic expansion valve, and/or the second throttle element 14 includes a second electronic expansion valve. The electronic expansion valve is easy to control, adjust, and control accurately, and can meet different levels of adjustment requirements.

Referring to FIG. 3, for a central air conditioner having a plurality of indoor units 1, in some embodiments, the liquid tubes 11 of each indoor unit 1 of the central air conditioner are provided with a corresponding first throttle element 12, and the air tube of the indoor unit 1 Each of the 13 is provided with a corresponding second throttle element 14.

Referring to Fig. 2, a temperature detecting device 4 for detecting the ambient temperature of the indoor unit 1 is provided in the heat exchanger 3 of the indoor unit 1. And/or a humidity detecting device 5 for detecting the ambient temperature of the indoor unit 1 is provided in the heat exchanger 3 of the indoor unit 1. The ambient temperature and humidity of the indoor unit 1 are detected in real time by the temperature detecting device 4 and the humidity detecting device 5.

Referring to Figure 3, in some embodiments, the first throttle element 12 and the second throttle element 14 are identical. The parameters such as the model number and the maximum number of steps are the same, which is convenient for overall adjustment control.

In the above control method, during cooling, the refrigerant first enters the first throttle element 12 to be throttled, enters the heat exchanger 3 of the indoor unit 1, and then enters the second throttle element 14 to throttle, and finally returns to the compressor.

The above control method will be specifically described below by taking an electronic expansion valve of 480 pls as an example.

Step 1: After the unit is powered on, the second throttle element (specifically, the electronic expansion valve) 14 maintains a maximum opening degree of 480 pls, and the first throttle element (specifically, an electronic expansion valve) 12 is controlled according to the superheat degree of the indoor unit 1, So that the indoor unit 1 does not have a liquid return phenomenon.

Step 2: Detect the air temperature and humidity in the room, and obtain the dew point temperature TL by detecting and calculating.

Step 3: If the ambient temperature is higher than or equal to TL, that is, the ambient temperature - TL ≥ 0 ° C, the room does not need to be dehumidified, but can be cooled. In this state, the low-pressure control of the outdoor unit is determined, and the evaporating temperatures of the indoor unit 1 are lowered by the two electronic expansion valves of the indoor unit 1 to achieve the purpose of reducing the air output of the single indoor unit 1. In this case, by reducing the number of steps of the second throttle element 14, the amount of refrigerant in the indoor unit 1 is increased, and the amount of heat absorbed from the outdoor unit is increased to reduce the temperature of the outlet air.

Step 4: If the ambient temperature is lower than TL, that is, the ambient temperature - TL < 0 ° C, the room needs to be dehumidified, and the refrigeration and dehumidification control can be performed. In this state, the low-pressure control of the outdoor unit has been determined. By controlling the two electronic expansion valves of the indoor unit 1, the evaporation temperature of the indoor unit 1 is raised to achieve the purpose of raising the room temperature and reducing the humidity. In this state, the second electronic expansion valve continues to maintain the maximum number of steps of 480 pls, reducing the number of steps of the first electronic expansion valve, so as to reduce the amount of refrigerant entering the indoor unit 1, so that the room can quickly reduce the air humidity, and keep the air temperature substantially stable. That is the purpose of dehumidification and refrigeration.

Referring to FIG. 2 and FIG. 3, another embodiment of the present disclosure provides an air conditioner for implementing the method for adjusting the evaporation temperature of an indoor unit of an air conditioner provided by any of the above technical solutions. Under the premise that the low pressure of the outdoor unit 6 of the system is constant, the air conditioner determines how to individually adjust the evaporation temperature of each indoor unit 1 based on the difference between the ambient temperature and the dew point temperature of each indoor unit 1.

The air conditioner includes a plurality of indoor units 1 connected in parallel, and the liquid pipe 11 of at least one indoor unit 1 is provided with a first throttle element 12, and the air tube 13 of the indoor unit 1 is provided with a second throttle element 14. The first throttle element 12 is for reducing the opening degree when the ambient temperature is lower than the dew point temperature to reduce the amount of liquid refrigerant entering the heat exchanger 3 of the indoor unit 1. The second throttle element 14 is for reducing the opening degree when the ambient temperature is higher than or equal to the dew point temperature to reduce the velocity of the gaseous refrigerant flowing out of the heat exchanger 3 of the indoor unit 1.

The above air conditioner includes a plurality of indoor units 1, and each of the indoor units 1 is connected in parallel with each other, and the working processes are independent of each other. The first throttle element 12 and the second throttle element 14 are provided on the gas pipe 13 and the liquid pipe 11 at both ends of the heat exchanger 3 of the indoor unit 1. The first throttle element 12 and the second throttle element 14 only control the evaporation temperature of the indoor unit 1 and do not affect the evaporation temperature of the other indoor units 1.

In the low-floor room, when the refrigerant enters the internal machine from the external machine, the refrigerant flows downwards, and the refrigerant in the connecting pipe becomes less and less. Thus, in the case where the internal machine is fully opened, the room in the lower floor is People often feel that there is no air in the air conditioning cooling / heat conditions. With the air conditioner provided in this embodiment, the amount of refrigerant in the indoor unit 1 is increased by reducing the number of steps of the second throttle element 14. In the refrigeration cycle mode, the low temperature liquid refrigerant of the indoor unit 1 is increased, so that the outlet air temperature is lowered, thereby achieving the cooling effect.

In a humid room, it is desirable to reduce the control humidity while ensuring that the air temperature is substantially constant, so that the number of steps of the first throttle element 12 can be reduced. In this state, the first throttle element 12 of the internal machine no longer performs PID control, but reduces the amount of liquid refrigerant of the indoor unit 1 according to the evaporation control of the indoor unit 1. When the air volume outputted by the fan 2 is constant, after the refrigerant evaporates, the outlet air temperature rises, and the control evaporation temperature is about 13 ° C. In this state, the outlet air temperature is between 17 ° C and 19 ° C, which not only removes the humid air, but also The cooling effect is guaranteed.

In some embodiments, the liquid tubes 11 of each indoor unit 1 are separately provided with a first throttle element 12, and the air tubes 13 of each indoor unit 1 are separately provided with a second throttle element 14. For each room in which each indoor unit 1 is located, the evaporation temperature required for cooling and dehumidification can be individually adjusted.

In this embodiment, the first throttle element 12 includes an electronic expansion valve. And/or, the second throttle element 14 includes an electronic expansion valve.

In the present embodiment, the first throttle element 12 and the second throttle element 14 are identical. The parameters such as the model number and the maximum number of steps are the same, which is convenient for overall adjustment control.

To facilitate control of the first throttle element 12 and the second throttle element 14, the air conditioner further includes a controller electrically coupled to the first throttle element 12 and the second throttle element 14, the controller for adjusting The opening of the throttle element 12 and the second throttle element 14.

Referring to Fig. 2, the air conditioner further includes temperature detecting means 4 for detecting the ambient temperature at which the indoor unit is located, and/or humidity detecting means 5 for detecting the humidity of the environment in which the indoor unit is located. The dew point temperature of the current environment is calculated by the values detected by the temperature detecting device 4 and the humidity detecting device 5. Of course, other methods can be used to obtain the dew point temperature.

Referring to Fig. 3, the air conditioner further includes a first compressor 7, a second compressor 8, an oil component 9, a four-way valve 10, a gas fraction 15, a radiator 16, and the like. The arrow A in Fig. 3 indicates the mounting direction.

In the description of the present disclosure, it is to be understood that the terms "center", "longitudinal", "transverse", "front", "back", "left", "right", "vertical", "horizontal", The orientation or positional relationship of the "top", "bottom", "inside", "outside" and the like is based on the orientation or positional relationship shown in the drawings, and is merely for the convenience of describing the present disclosure and simplifying the description, rather than indicating or implying The device or component referred to must have a particular orientation, is constructed and operated in a particular orientation, and thus is not to be construed as limiting the scope of the disclosure.

It should be noted that the above embodiments are only used to illustrate the technical solutions of the present disclosure and are not to be construed as limiting thereof; although the present disclosure will be described in detail with reference to the preferred embodiments, those skilled in the art should understand that Modifications of the specific embodiments disclosed are intended to be equivalent to the equivalents of the technical features of the present disclosure.

Claims

A method for adjusting an evaporation temperature of an indoor unit of an air conditioner, comprising the steps of:

Determining whether the ambient temperature of the indoor unit is higher than or equal to the dew point temperature;

If the ambient temperature is lower than the dew point temperature, reducing the opening degree of the first throttling element of the liquid pipe provided in the indoor unit to reduce the amount of liquid refrigerant entering the heat exchanger of the indoor unit; if the ambient temperature is high At or equal to the dew point temperature, the opening of the second throttle element of the air pipe provided in the indoor unit is reduced to reduce the speed at which the gaseous refrigerant flows out of the heat exchanger of the indoor unit.
The method for adjusting the evaporation temperature of an indoor unit of an air conditioner according to claim 1, wherein if the ambient temperature is lower than the dew point temperature, the opening of the second throttle element of the air tube provided in the indoor unit is maintained .
The method for adjusting an evaporation temperature of an indoor unit of an air conditioner according to claim 1, wherein if the ambient temperature is higher than or equal to the dew point temperature, the opening of the first throttle element of the liquid pipe provided in the indoor unit is maintained. The degree is unchanged.
The method for adjusting an evaporation temperature of an indoor unit of an air conditioner according to claim 1, wherein the first throttle on the liquid pipe of the indoor unit is reduced in a manner proportional to a difference between a dew point temperature and an ambient temperature The opening of the component.
The method for adjusting an evaporation temperature of an indoor unit of an air conditioner according to claim 1, wherein the second throttle element on the indoor air tube is reduced in proportion to a difference between an ambient temperature and a dew point temperature Opening.
An air conditioner, comprising:

a plurality of parallel indoor units (1), at least one liquid pipe (11) of the indoor unit (1) is provided with a first throttle element (12), and a gas pipe (13) of the indoor unit (1) is provided Second throttle element (14);

Wherein the first throttling element (12) is configured to reduce the opening degree when the ambient temperature is lower than the dew point temperature to reduce the amount of liquid refrigerant entering the heat exchanger (3) of the indoor unit (1); The second throttle element (14) is for reducing the opening degree when the ambient temperature is higher than or equal to the dew point temperature to reduce the velocity of the gaseous refrigerant flowing out of the heat exchanger (3) of the indoor unit (1).
The air conditioner according to claim 6, wherein each of the liquid tubes (11) of the indoor unit (1) is provided with one first throttle element (12), and each of the indoor units (1) The air tubes (13) are each provided with one of the second throttle elements (14).
The air conditioner according to claim 6, wherein the first throttle element (12) comprises an electronic expansion valve; and/or the second throttle element (14) comprises an electronic expansion valve.
Air conditioner according to claim 6, characterized in that said first throttle element (12) and said second throttle element (14) are identical.
The air conditioner according to claim 6, further comprising:

a controller coupled to the first throttling element (12) and the second throttling element (14) for adjusting the first throttling element (12) and the second throttling element (14) The opening degree.
The air conditioner according to claim 6, further comprising:

a temperature detecting device (4) for detecting an ambient temperature of the indoor unit (1); and/or,

A humidity detecting device (5) for detecting the humidity of the environment in which the indoor unit (1) is located.
The air conditioner according to claim 6, wherein said air conditioner comprises a central air conditioner.